Sealing means for soot blowers amd the like



Aug. 27, 1957 w. F. CANTIERI ET AL 2,804,032

SEALING MEANS FOR SOOT BLOWERS AND THE LIKE Filed Nov. 7, 1952 United States Patent i SEALING MEANS FOR SOOTBLDWERS AND THE LIKE William -E..Cantieri,,Le.Roy.S. De Mart, and Jacob Fogel, Lancaster, Ohio, assignorsto. Diamond Power Specialty CbrporatiomLancaster, Ohio, acorporationof Qhio Application Novemberfl, 1952; SerialflNo. 319,3-/4

' This. invention relates. to a sealing. device and, more particularly, to. an improvedsealing device adapted for use. withwretractable, soot blowersand thelike.

Anobject of-thexinvention isto overcome the disadvantages inherent in conventional sealing devices and to, provide an improved.sealing.device adapted to pre vent :the. escape .of gases from-the boiler furnace through theiopening in the furnace wall which. is provided to accommodate the lance tube of a retractable soot blower.

Another object'of the inventionisgtoprovide an improved; sealingdevice particularly adapted for use with positive pressureboilers.

Another. object of the, invention is? to provide, ,an improved sealing device adapted to preventthe escape of gases; through=such opening eventhough he retractable lance tube; isi bent: or warped;

Another. objectoftheinventionisto provide; an imthe Iancetubeof aretractable soot blower adjaeentthe wallbox end in which air ismaintained-under pressure in" excess of the pressure. in theboiler furnace. Since the operating pressure of" the furnace isgreater than the ambient atmospheric pressure, the-present invention provides means which compensates for such difference in pressure thereby enabling approximately thesame amount of pressurized sealingair to flow fromthe aforementioned]chamber-through the wallb'ox into the furnace as flows from the chamber to the atmosphere, so

a sto provide an air' seal which: effectively prevents the escape of hot'gases fromjthe furnace; The present inventionals'o provides means for forming an air seal in the event thelance ;tube ofthe sootblower is completely removed from the wallbox" of the boiler. furnace.

With the above" as'wellas other. and in.certain cases more detailediobjects; in view; which will become apparent' from the following description and the appended claims, a preferred but illustrative embodiment" of the invention is: illustrated" in the accompanying drawing throughoutthe several views ofwhich corresponding reference characters designate corresponding, parts and wherein:

t Fig. l'is" a; side-elevational' yiewofa soot blower sealing-installation incorporatingthe presentinvention, with 2,804,032 Patented Aug 27, .1957

ice

applied to the lance tube of a soot blower; and Fig 2 is. a. sectional. view taken. substantially on: the line l- 2. ofiFig. 1 andslo'okingin the directionv of.,the arrows.

Referring to the drawing; .,a preferred. embodiment.- of the invention is shown incorporated. in" at seal. for a -retractable soot-blower ofyatknown type which is1shown in installedwrelation, with respect to, a boiler, which; is fragmentarilyillustrated.. The; details ofthe boiler and blower formlno part of the present invention. While along-travel blower is; shown,;this-is merely to;typify portions. in section, and other. portions broken away, as

an-important use-of, the invention. The blower instal-' lation includesastationary supporting I-beam 1.0mmjecting;horizontally; andiperpendi'cularly from'the boiler wall 18. A wallbox;.16;is securedby pinz12. and an upwardlyextendingbracket 14 to the beam 10.:

Thesretractable' and. rotatablelance tube 20 is. also carried-by th'erbeam 10, so that alignment ismaintained between the lance-tube: and wallbox. Therotationaland sliding. movementzislimparted to the lance tubewby any suitable. or conventional. driving means. (not shown). The lancetube 20. is projectable into, and retractablefrom, the: boiler-furnace through. the wallbox 16 which hasan opening: 17? coaxial with, butsomewhat larger in diameter than, the lancetube 20; Whenthe blower is operated, compressed air, steam, solid pellets and/orother cleaning-mediumis supplied through the lancetubeand discharged fromtthe nozzle end 21 thereof againstthe boiler surfaces to be cleaned, which may include the Water wall tubes, as-22t A housing 24, having an annular, internal chamber 25 and a substantially axial bore 26, ismounted' on1the outer wall 28 ofthe wallbox and secured thereto by bolts such as 30. and 32, the bore 26being coaxial with the opening 17 in;the Wallbox. A sleeve member 34 having an outwardly extending flange portion'36is fitted in the bore 26 and' secured to the outer end:wa1l 38by bolts such as 40' and 42-which pass through the flange portion 36 .and threadably engage openings in the wall 38-; Sleeve member 34 is provided with aninternalannular groove 35. having circumferentially spaced holes, such as 44', therein communicating with the chamber 25.

Pipe fitting openings, such as 48.and 50 are formed in'the outer walls of .housing 24 and a supply pipe, "as 5 1, is attached to the most readily accessible socket opening inthe particular installation, the othersockets being, of. course, plugged. Compressed air is fed tothe chamber 25'through pipe 51, and then passes through the holes, such as 44, and along the periphery. of the lance tube which passes throughthe sleeve member 34. The internal diameterof the portion of the..,sleeve.between groove, 351and the furnaceis somewhat greater than the internal diameter of, thesleeverportion between the internalgroove 35. and. the. atmosphere; Greater clearance; is: thereby provided inthe-annular area. designated 52 between the: lance tubeand the. furnace end of. the sleeve member 34 than .is.provided imthe annu- 1211 area 54 between th'elance tubeand the outer end portion 54 of thesleevemember. The airpressure at 52is somewhat. greater than the operating pressureof the furnace,,which is greater than, the ambient, atmospheric pressure at 54; and the clearance areas are proportioned so. thatapproximately the same amount. of air flows from the chamber 25, through the holes, such as 44, along the periphery'ofthe lance tube, andthrough the clearancearea at 52 into the. wallbox opening. 17

as flows from the chamber, through the holes, along the periphery of. the lance tube and through the clearance area'at'541to the atmosphere. a I

The compressedair flowing into the furnace forms an sitely disposed, inwardly extending brackets 62 and 64,

the outer end portions of which are pivotally attached to the plate 58 by studs 66 and 6 8 and nuts 70 and 7 2. 'A pair of tapered rollers 74 and 76 are rotatably -mounted on rollerpins 78 and 80 which in turn are mounted in the inner end portions of the brackets 62 and 64, respectively, the pins being secured by set screws,

such as 82, threadablyfitted in the brackets and engaging a recess in the enlarged collar portion 84 provided on theouter end portion of each pin.

Since the lance tube 20 is rotated in one direction during the projection into the furnace and is rotated in the opposite direction during the retraction from the .furnace, the rollers 74 and 76 are set at an angle to the axis of the lance tube, the angle corresponding to the pitch of the helix represented by such rotary and longitudinal movement of the lance tube so as to reduce the frictional contact between the rollersand the tube. Because of the angular positioning of the rollers, they are formed in the shape of a truncated cone to insure substantially line contact with the tube.

The inner end portions of the brackets 62 and 64 are supported on adjusting bolts '86 and 88, threada-bly fitted in the forwardly projecting horizontal plate 90 which is welded or otherwise rigidly secured to the plate 58, the bolts 86 and 88 being locked in the selected adjusted position by locking nuts 92 and 94, respectively.

In order to prevent the escape of gases from the furnace in the event the lance tube is completely withdrawn from the furnace, as for repair or replacement, an internal annular chamber 96 is provided in the Wallbox 16 at a position near but spaced from the outer wall thereof. A bushing member 98, adapted to receive the lance tube 20, is fitted in the opening 17 of the wallbox, the inner portion of the.bushing having tongues, such as 100, which are welded or otherwise rigidly secured to the wall water tubes 22.- A relatively large number of closely peripherally adjacent inwardly convergent duct openings, such as 162 and 104, extend through the wall of bushing 98 and communicate with chamber 96. Compressed air is adapted to be supplied to the chamber 96 through a supply pipe 107 threada'bly attached to the wall box as at 1&5 and is discharged from holes 102 in the form of a conelike screen at sufficient velocity to prevent outflow of furnace gases therethrough, even if the lance tube is backed away for servicing. A suitable hand valve (not shown) may enable control of the air supply to the air screen-discharge openings, as will be apparent. It has been found desirable to allow discharge of a slight amount of air through openings 102 at all times while the boiler is in service, to protect the openings against fouling.

From the above description it will be observed that the entire sealing device will operate at a relatively low temperature because of the flow of air therethrough and also'because of the cooling effect obtained as the compressed air expands to the lower pressures, thereby insuring relatively long life for the device.

While a preferred. embodiment of the invention has been shown and described, it will be understood that various changes and modifications may be made without departing from the spirit andscope of the invention.

What is claimed is:

1. Incom'bination with a boiler furnace having a 'wall defining an opening, a lance tube-projectable into and retractable from said boiler furnace through the opening defined by said wall, a sealing device adapted to prevent the escape of gases from said furnace through the opening defined by said wall, said device comprising a tubular housing encompassing said lance tube at a position adjacent said furnace and defining a bore open at each end and through which the lance tube projects, means Securing one end of said housing to said wall in gas-tight relationship with the open ends of the bore of said housing aligned with the opening defined by said wall, said housing defining an annular chamber wherein air is maintained under pressure in excess of the pressure in said furnace, means for supplying air under pressure to the chamber defined by said housing, means carried by said housing and defining clearance areas spaced longitudinally of said lance tube permitting air to flow from the chamber defined by said housing through the bore of the housing simultaneously into said furnace and to atmosphere for compensating for the difference in the pressure of the gases in said furnace and the pressure of the ambient atmosphere whereby the air flowing from the chamber defined by said housing opposes communication of the gas pressure with the atmosphere through the opening defined by said wall, means secured to said housing for supporting said lance tube, said support means comprising a pair of oppositely disposed brackets pivotally attached at the outer end portions thereof to said housing, a pair of rollers rotatably mounted on the inner end portions of said brackets and bearing against said 'lance tube, and means secured to said housing for supporting said brackets in a selected adjusted position. 1

2. In combination with a boiler furnace having a wall defining an opening, a lance tube projectable into and retractable from said boiler furnace through the opening defined by said wall, a sealing device adapted to prevent the escape of gases from said furnace through the opening defined by said wall, said device comprising a tubular housing encompassing said lance tube at a position adjacent said furnace and defining a passageway open at each end and through which the lance tube projects, means securing one end of said housing to said wall in gas-tight relationship with the open ends of the passageway of said housing aligned with the opening defined by said wall, said housing defining an annular chamber communicating with the passageway defined by said housing and wherein air is maintained under pressure in excess of the pressure in said furnace, means for supplying air under pressure to the chamber defined by said housing, means carried by said housing and defining clearance areas in the housing passageway spacedlongitudinally of said lance tube permitting air to flow from the chamber defined by said housing through the housing passageway simultaneously into said furnace and to atmosphere for compensating for the difference in the pressure of the gases in said furnace and the pressure of the ambient atmosphere whereby the air flowing from the chamber defined by said housing opposes communication of the gas pressure with the atmosphere through the opening defined by said wall, means secured to said housing for supporting said lance tube, said support means comprising a pair of oppositely disposed brackets pivotally attached at the outer end portions thereof to said housing, a pair of tapered rollers rotatably mounted in the inner end portions of said brackets and bearing against said lance tube, the axis .of each of said rollers being offset with respect to the axis of said lance tube, and means secured to said housing for supporting said brackets in a selected adjusted position.

3. In combination with a boiler furnace provided with a wall box having an opening therein to accommodate a lance tube, a lance tube projectable into and retractable from said furnace through the opening in said wall box, means for preventing the escape of gases from said furnace through the opening in said wall box, saidmeans comprising a tubular housing; encompassing said lance tube at a position adjacent said furnace and defining a bore open at each endthrough which-the lance tube projects, means securingone end of said housing to saidwall box in gas-tight relationship with the open ends-of the bore of said housing alignedwith theopening in said Wall box, said housing defining an annular chamber communicating with the bore of 'said housing and whereinair is maintained under pressure in excess of thepressure in said furnace, means for'supplying air under pressure to the chamber defined by said housing, means carried-by said housing and defining clearance-areasinthebore ofsaid housing spaced longitudinally of said lancetube permitting air tofi'ow from the chamber through-the bore of,

said housing simultaneously-t into said furnace and to atmosphere for: compensating: for the difference in pressurerof the gases in said furnace and the pressure of the ambient atmosphere whereby the air flowing from the chamber defined-by said housing opposes communication of the. gas pressure with the atmosphere, saidwall, box defining an annular chamber communicating with the opening insaid walltbox and; wherein air: is maintained under pressureiin excess of, the pressure in saidfurnace, means for supplyingairt under pressure to the annular chamber in saidpwallbox, and means for; directing the airfrom thechamberydefined bysaid: wall box into said furnace, throughithe opening in said, wallbox whereby the: air from the; chamber defined by, said wall box opposes, communicationofthe gases in said furnace with, the atmosphere.

4. Incombination with aboiler furnace provided with a wallrbox havingwan opening therein to accommodate a furnace through the opening defined byt said wall box, said, meansI comprising a tubular housing encompassing saidlance tube atL-a position adjacent saidfurnace and.de-

fining a bore open atreachtend through WhlChlthG lance,

tubeprojects, means securingone endof said housing to said ,wall box in gas-tight relationship .with the open ends of the bore of said housing aligned withtheuopeningt defined by said wall box, said housing defining an annular chamber communicatingwith thetbore of said housing and wherein air is maintained under pressure in excess of the pressurein-said furnace, means for supplying air under pressure to, the, chamber in, said housing,- means carriedby, said housing andtdefiningclearance areas, in the boreof; said housingspaced longitudinally of said lancegtubeppermitting air to fiowfrom the chamber, in said housing through the bore of--sa;id housing; simultaneously into said furnace and to atmosphere for compensating for the difierence in pressure of the gases in said furnace and the pressure of the ambient atmosphere whereby the air flowing from the chamber in said housing opposes communication of the gas pressure with the atmosphere, said wall box defining an annular chamber communicating with the opening in said wall box and wherein air is maintained under pressure in excess of the pressure in said furnace, means for supplying air under pressure to the annular chamber in said wall box, means for directing the air from the chamber in said wall box into said furnace through the opening in said wall box whereby the air from the chamber in said wall box opposes communication of the gases in said furnace with the atmosphere, means secured to said housing for supporting said lance tube, said support means comprising a pair of oppositely disposed brackets pivotally attached at the outer end portions thereof to said housing, a pair of rollers rotatably mounted on the inner end portions of said brackets and bearing against said lance tube, and means secured to said housing for supporting said brackets in an angularly adjusted position.

5. In combination with a boiler furnace provided with a Wall box having an opening therein to accommodate a lance tube, a lance tube projectable into and retractable from said furnace through the opening in said wall box,

means for preventing the escape of gasesfrom said furnace through theopeningdefined by said wall box, said means comprising a tubular housing encompassing said lance tube at a position adjacent said furnace and defining a ber communicating with the bore of said housing and saidifurnacerthrough the. opening: in saidwall box; wherewherein air is maintained under pressure in excess of the pressure insaidfurnace, means for supplying air under pressure to thechamber. in said housing, means carried by said housing and defining clearance areas in the bore of said housingspacedlongitudinally of said lance tube permitting airto-flow from the chamber in said housing through the; bore of said housing simultaneously into said furnace and to atmosphere forcompensating for thedifferencein pressureof the gases in said furnace andthe pressure of the ambient atmosphere whereby the air flowing from the chamber in said housing opposes communication of the gas pressure=with the atmosphere,

said wall box= defining an annular chambercommunicating with theopening in said.- wall box and wherein air ismaintained under: pressure-in excess of the pressure in said furnace, means-for supplyingair under pressure to the annularchamber in said wall box, means for directing: the airfrom the chamber in said wall box into bythe air from the=chamben in saidxwall box opposes communicatiomof;theigases insaidxfurnacewith the atmosphere, means: 01711 supporting said' lance tube, said support: means; comprising a; pair. off oppositely, disposed brackets pivotallyattached at the outer endportiousthere- Gift to said". housing, az. 'pair' oft tapered rollers rotatably mounted in: the; inner: end; portions of 1 said 1 brackets and bearingyagainst saidilance tube the axis of each of said rollers beingiofiisetawith respect toythe axistofj said lance tube, and: means secured tto said housing for-supporting said brackets in; an, t angularly adjusted position; i

6, In combination with; a-boiler furnace -provided with a wallgboxihavingan opening thereiniadapted to accomtmodatet a lance; tube, alance tube projectableinto and retractable from said furnace through said opening, means for: preventing, the; escape of gases from. said furnace throughithe-walhboxi opening,,said means comprising a tubular housingdefining a: horizontally extending, bore open at; each; end, said housing also defining an annular chamber communicating with the bore of. said housing and wherein airis? maintained under. pressure in excess Of: theipress l filin said furnace, means forsupplying air under pressure to the-chamben in saidhousing, means securing one end of said housing to said wall box in gastight relationship with the open ends of the bore of said housing aligned with the opening defined by said wall box, a sleeve member fitted in the bore of said housing and adapted to receive said lance tube, said sleeve memher having circumferentially spaced openingsat a position near but spaced from the ends thereof interconnecting the chamber defined by said housing with the bore of said housing, said sleeve member defining clearance areas spaced longitudinally of the lance tube and permitting air to how from the chamber defined by said housing through the openings in said sleeve member and the bore of said housing simultaneously into said furnace and to atmosphere whereby such air opposes communication of the gases in the furnace with the atmosphere.

7. A sealing device for soot blowers and the like comprising a housing defining an annular chamber, means for supplying compressed air to the chamber defined by said housing, a horizontally extending sleeve member fitted in said housing and defining a bore open at each end and adapted to accommodate therein a lance tube,

said sleeve member also defining a plurality of centrally disposed circumferentially spaced openings interconnecting the bore thereof with the chamber defined by said housing, the diameter of said sleeve member at one end thereof being less than the diameter at the opposite end thereof whereby said sleeve member defines spaced clearance areas permitting air to flow from the chamber defined by said housing through the openings in said sleeve member and proportionately through opposite ends of the bore of said sleeve member when a lance tube is inserted therein, means secured to said housing for supporting a lance tube, said support means comprising a pair of oppositely disposed brackets pivotally attached at the outer end portions thereof to said housing, a pair of tapered rollers rotatably mounted in the inner end portions of said brackets, the peripheral surfaces of said rollers being disposed within a cylindrical projection of the bore of said sleeve member and being adapted to bear against a lance tube when a lance tube is inserted in said sleeve member, the axis of each of said rollers;

being offset with respect to the longitudinal axis of said sleeve member, and means secured to said housing for supporting said brackets in an angularly adjusted position.

8. A sealing device adapted for use with a boiler furnace, said device comprising a wall box adapted to be mounted in an opening in the furnace wall, said Wall box having an opening therein adapted to accommodate a lance tube, a tubular housing defining an annular chamber, a horizontally extending sleeve member fitted in said housing and defining a bore open at each end and adapted to accommodate a lance tube, said sleeve member being provided with a plurality of centrally disposed circumferentially spaced openings interconnecting the bore of the sleeve member with the chamber defined by said housing, the diameter of one end of said sleeve member being less than the diameter of the opposite end of said sleeve member whereby said sleeve member defines clearance areas spaced longitudinally thereof and permitting air to flow from the chamber defined by said housing through the openings in said sleeve member and the bore thereof simultaneously into said furnace and to atmosphere, means for securing said housing to said wall box in gas-tight relationship with the open ends of the bore of said'sleeve member aligned with the opening in said wall box, said wall box defining an annular chamber at a position near but spaced from one end thereof, a bushing member fitted in said wall box opening and defining a bore, said bushing member being provided with circumferentially spaced inclined openings interconnecting the bore thereof with the chamber in said wall box, means for supplying compressed air to the chamber defined by said housing and to the chamber defined by said wall box, and means secured to said housing for supporting said lance tube.

, end and adapted to accommodate a lance tube, said sleeve member being provided with a plurality of centrally disposed circumferentially spaced openings interconnecting the bore of the sleeve member with the chamber defined by said housing, the diameter of one end of said sleeve member being less than the diameter of the opposite end of said sleeve member whereby said sleeve member defines clearance areas spaced longitudinally thereof and permitting air to flow from the chamber defined by said housing through the openings in said sleeve member and the bore thereof simultaneously into said furnace and to atmosphere, means for securing said housing to said wall box in gas-tight relationship with the open ends of the bore of said sleeve member aligned with the opening in said wall box, said wall box defining an annular chamber at a position near but spaced from one end thereof, a bushing member fitted in said wall box opening and defining a bore, said bushing member being provided with circumferentially spaced inclined openings interconnecting the bore thereof with the chamber in said wall box, means for supplying compressed air to the chamber defined by said housing and to the chamber defined by said wall box, means secured to said housing for supporting said lance tube, said support means comprising a pair of oppositely disposed brackets pivotally attached at the outer end portions thereof to said housing, a pair of tapered rollers rotatably mounted in the inner end portions of said brackets, the peripheral surfaces of said rollers being disposed within a cylindrical projection of the bore of said sleeve and adapted to bear against a lance tube when a lance tube is inserted in said sleeve, the axis of each of said rollers being offset with respect to the axis of said sleeve, and means secured to said housing for supporting said brackets in an angularly adjusted position.

References Cited in the file of this patent UNITED STATES PATENTS 1,567,416 Cagwin Dec. 29, 1925 2,018,242 Von Schlippenbach .4 Oct. 22, 1935 2,528,671 Selnik Nov. 7, 1950 2,545,886 Kooistra Mar. 20, 1951 2,622,549 Fletcher Dec. 23, 1952 

